The present experiment examined whether leaders high in charisma are able to motivate decision-makers to cooperate more in a public goods dilemma. On the basis of charismatic leadership theories, it was expected that a charismatic leader would be able to transform people's motives beyond self-interest, consequently increasing cooperation. This transformation effect was expected to occur among individuals aimed at maximizing their own self-interest (i.e., pro-selfs), but not among those aimed at maximizing joint or collective outcomes (i.e., pro-socials). Furthermore, leader's charisma was experimentally manipulated by means of describing the leader as either self-sacrificing or benefiting. The results revealed that self-sacrificing leaders, contrary to benefiting leaders, were perceived as more charismatic and were able to motivate decision-makers to cooperate more. The latter effect appeared to be more pronounced among pro-selfs rather than pro-socials, as such supporting the transformational idea of charismatic leaders. Further results showed that this behavioral effect was mediated by perceptions of legitimacy. The meaning and conception of charismatic leadership in decision-making situations are discussed by using insights from the social dilemma and charismatic leadership literature.